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ComPac 9/04-12
Figure 4. H205A Temperature Control Points
1.9 E
CONOMIZER
C
OMPONENTS
(C
OM
P
AC
®
II
A/C O
NLY
)
Damper Actuator:
The damper actuator is a 24V motor that modulates the position of the damper blade. It is
capable of driving a full 90 degrees within 90 seconds. The assembly has a spring return to
close the damper during power outage.
Controls:
The economizer is controlled by the H205A enthalpy control or optional dry bulb sensor.
H205A Economizer Changeover Control:
The H205A enthalpy controller responds to the total heat content of the outdoor air to provide
changeover to outside air for free cooling. The change point (factory set at "D") is adjustable
from 53°F @ 50% RH (full counterclockwise) to 78°F @ 50% RH (full clockwise). Refer to
Figure 4 and Figure 5.
Once the H205A has selected outside air, the mixed air sensor will limit the air temperature
CONTROL
CONTROL POINT*
CURVE
AT 50% RH
A
72°F/23°C
B
68°F/20°C
C
63°F/17°C
D
58°F/14.5°C
Full CCW is 55°F
*Approximate Deg.
